A son took his old father to a restaurant for an evening dinner. His father was very old and weak. So while his father was eating, he always dropped(落下) food on his clothes. Many people in the restaurant watched him in disgust(厌恶地), but his son kept quiet.

    After he finished eating, his son quietly took him to the washroom, washing the food and the other dirty things carefully. When they came out, the whole restaurant was watching them in silence.  The son paid the waiter for their food and started walking out with his father.

    At that time, an old man in the restaurant called out to the son and asked him, "Don't you think you have left something behind？"

    "No sir, I haven't," the son replied.

    "Yes, you have! You left a lesson for every son and hope for every father," the old man said.

    The restaurant went silent. No one said anything.

    Mike teaches a very basic programming (编程) course to a group of students. They are all very interested in computers.

    One day, Mike told his students to write a short program on their computers. After writing it, they only needed to type "R", "U" and "N" and press "enter" to see the program run.

    Soon, a student sitting in the back of the classroom put up her hand. She said, "I did what you said, but it didn't work." Mike knew that students sometimes make mistakes when typing. So he suggested that the student retype (重新输入) "R", "U" and "N".

    A few seconds later, the student's hand went up again. "It still doesn't work," she said. This time. Mike went to her to see what the problem was. To his surprise, he found that instead of typing "RUN", the student had typed "ARE YOU IN"!

    Alan Smith is blind. He teaches blind children in his country. To show the world that the blind can also do something amazing, he walked across the world's largest salt desert, Salar de Uyuni, only with the help of a GPS.

    Walking across the desert is not easy for an able-bodied person, let alone(更不用说) a blind man. Before setting off, Alan spent three years training for the journey. He studied everything he could find about the place and asked for advice from other travelers. During his journey, he only took water, food and sleeping bags. He walked about 20 kilometers a day. He showed great perseverance(毅力)and finished the 140-kilometer journey in just seven days.

    The brave teacher thought his week-long journey was wonderful. He said, "The journey was quite good. There were snow storms and winds, but luckily I made it."

    Mrs. Brown lives in a small village. Her husband is dead. She has a son but no daughters. His name is John and he is twenty-five. After John finishes college (大学), he gets work in a big city, New York, and he lives there. It's quite a long way from his mother's home, and she is not happy about it. But John says, "There is no good work for me in this small village, Mother, and I can get a lot of money in New York. Then I can give much to you. "

    One day Mrs. Brown is very angry. She takes a train to her son's house in New York. Then she says to him. "John, why do you never call me?"

    "But mother," John laughs (笑) and says, "You don't have a telephone."

    "No," she says, "I haven't, but you have one."